Over the last years, virtual networking has evolved towards becoming a dominant platform for the deployment of new services and applications such as large-scale data sharing, multimedia services, application-level multicast communication. A consequence of this evolution is that features like robust routing, efficient search, scalability, decentralization, fault tolerance, trust and authentication have become of paramount importance. Since network virtualization basically represents the process of combining resources of different types, two distinct aspects stand out. The first aspect is virtualization of hardware on network entities, while the second being in essence a virtualized networksuch as an overlay network. In this context, overlay networks act as enablers by providing the addressing and routing substrates needed to implement a virtualized network structure. In this paper, we focus on the second aspect of network virtualization and consider the specific case of structured overlay networks with a particular focus on Content Addressable Networks (CAN). An investigation of the existing approaches for structured P2P overlay networks is provided, where we point out their advantages and drawbacks. The essentials of CANarchitecture are presented and based on that, we report on the implementation of a CAN simulator. Our initial goal is to use the simulator for investigating the performance of the CAN with focus on the routing algorithm. Preliminary results obtained in our experiments are reported as well. The results indicatethat greedy routing algorithms perform better than non-greedy algorithms.